Resistens mot grönmögel hos äpple

Äpple är gott och nyttigt, och allt fler konsumenter frågar efter svensk frukt i affärerna. Men tillgången är inte så stor eftersom svenska odlare endast producerar 20% av de äpplen vi äter i Sverige. Resten importeras från utlandet, där klimatet är gynnsammare, arbetskostnaderna lägre och tillgången på tillåtna växtskyddsmedel större. Konsumenterna är kanske beredda att betala lite extra för svensk frukt men man förväntar sig då att kvaliteten ska vara på topp: vackra, friska och välsmakande frukter

Review of the Impact of Apple Fruit Ripening, Texture and Chemical Contents on Genetically Determined Susceptibility to Storage Rots

Fungal storage rots like blue mould, grey mould, bull's eye rot, bitter rot and brown rot destroy large amounts of the harvested apple crop around the world. Application of fungicides is nowadays severely restricted in many countries and production systems, and these problems are therefore likely to increase. Considerable variation among apple cultivars in resistance/susceptibility has been reported, suggesting that efficient defence mechanisms can be selected for and used in plant breeding. These are, however, likely to vary between pathogens, since some fungi are mainly wound-mediated while others attack through lenticels or by infecting blossoms. Since mature fruits are considerably more susceptible than immature fruits, mechanisms involving fruit-ripening processes are likely to play an important role. Significant associations have been detected between the susceptibility to rots in harvested fruit and various fruit maturation-related traits like ripening time, fruit firmness at harvest and rate of fruit softening during storage, as well as fruit biochemical contents like acidity, sugars and polyphenols. Some sources of resistance to blue mould have been described, but more research is needed on the development of spore inoculation methods that produce reproducible data and can be used for large screenings, especially for lenticel-infecting fungi

Study of aqueous extract of three medicinal plants on cell membrane–permeabilizing and their surface properties

The aim of this study was to evaluate the effect of aqueous extract of three medicinal plants, Artemisia dracunculus L, Cuminum cyminum L and Heracleum persicum Desf, which contain saponins on biological membrane. Also in this study, some of their physicochemical properties were studied. At the first step, the aqueous extract of the plants were prepared, using maceration and then the extracts were lyophilized. 0.2 ml of RBC was added to 0.2 ml of different concentrations of each extract in McIvan’s buffer, and then incubated in two different times and temperatures. The absorbance of the samples was determined by UV spectrophotometer. Among the three studied extracts, A. dracunculus L showed the highest hemolytic effect and the Heracleum persicum Desf showed the lowest one. The values of emulsification Index (E24) and foam formation activity (Fh) showed for each extract the properties of surface activity. Regarding the results of this study, when considering the health of consumer, the use of aqueous extract of H. persicum Desf, with low hemolytic effect is preferred in pharmaceutical preparation. But if the hemolytic effect were considered, the use of aqueous extract of A. dracunculus L, with great hemolythc effect in comparison to the two other extract, is preferred

Screening Three Strains of Pseudomonas aeruginosa: Prediction of Biosurfactant-Producer Strain

Problem statement: The chemical surfactants have some disadvantages; especially, toxicity and no biodegradability. Approach: Biosurfactants were the structurally diverse group of surface-active molecules synthesize by micro-organisms. The microbial surfactants were interesting, because of the biodegradable and have many applications in industry, agriculture, medicine. Results: In the present study, the production of biosurfactant by three strains of Pseudomonas aeruginosa (PTCC 1074, 1310 and 1430) was investigated. The hemolytic and foam forming activity of different strains were studied and consequently, P. aeruginosa PTCC 1074 was selected as the suitable strain. P. aeruginosa PTCC 1074 was grown in the nutrient broth medium and biosurfactant production was evaluated every 24 h by emulsification index and surface tension for the best of production time. After that, in order to get maximum production of biosurfactant, the selected strain was grown with different additives in nutrient broth and the best culture medium was found. The biosurfactant was isolated from the supernatant and its amphipathic structure was confirmed by chemical methods. Conclusion: Biosurfactant produced by Pseudomonas aeruginosa PTCC 1074 would be considered as a suitable surfactant in industries due to its low toxicity

Evaluating the toxicity of permeability enhanchers of polyethylene glycol brij ethers surfactants group on cellular membranes and some of their physicochemical properties

The aim of this study is to evaluate the effect of polyethylene glycol brij ethers surfactants group on red blood cells as a model for biological membranes. Also in this study, physicochemical properties including emulsification index (E24), foam producing activity (Fh) and critical micelle concentration (cmc) were studied. Surfactant solutions were prepared in McIvan’s buffer in specific concentrations. 0.2 ml of red blood cells (RBC) was mixed with 0.2 ml of each surfactant solution. The four surfactant solutions had each been incubated differently at two different temperatures for three different times. Each test was done six times. The results were presented as mean absorbance ± the standard deviation. E24, Fh and cmc were also determined for each surfactant solution. All of the surfactant solutions showed hemolytic activity. In comparison with the four studied surfactants, brij 56 had the highest hemolytic effect and brij 72 the lowest. The values of E24 and Fh had good correlation with hydrophilic-lipophilic balance values. According to the results of this study, brijs should be used at concentrations lower than cmc in formulations. Also, according to the results, the use of brijs with low hemolytic effect such as brij 72, is preferred in pharmaceutical preparations

Investigation of cellular hydrophobicity and surface activity effects of biosynthesed biosurfactant from broth media of PTCC 1561

Biosurfactants as surface active molecules that are synthesized by microorganisms. These substances include many advantages in comparison with chemical surfactants. For instance they have lower toxicity, higher biodegradability, better environmental compatibility, higher foaming activity, and specific activity at extreme temperatures, pH ranges, and the ability to be synthesized from renewable feed stocksin. In this study, the production of biosurfactant, produced by PTCC 1561 was studied. This bactrium was grown in a nutrient broth medium and the production of biosurfactant was evaluated by the surface tension and emulisification index (E24), each 24 h. The production of biosurfactant was studied in different conditions, including time of incubation, temperature, aeration rate and presence of several additives containing mineral salts and hydrocarbons. Finally, the optimum condition for production of the biosurfactant was determined and the biosurfactant identity was investigated using chemical and spectroscopy methods. The maximum biosurfactant production by Pseudomonas aeruginosa PTCC 1561, was exhibited when it was grown in Brain Hearth Broth medium containing Fecl3, ZnSO4, FeSO4, starch and olive oil incubated in a 200 rpm shaker incubator at 37°C for 24 h . The structure of produced biosurfactant sugar-lipid was confirmed by chemical and spectroscopy methods

Investigating the effects of various additives on surface activity and emulsification index of biosurfactant resulting from broth media of Bacillus subtilis PTCC 1023

Surfactants are amphipathic molecules which reduce surface tension and are widely used in pharmaceutical, cosmetic and food industries. In the present study, the production of biosurfactant by Bacillus subtilis PTCC 1023 was studied. B. subtilis was grown in the nutrient broth medium and biosurfactant production was evaluated by measuring the surface tension and emulsification index (E24) each 24 h. The bacterium’s biosurfactant production was investigated in different status with variable factors such as incubation time, temperature, aeration rate and presence of several additives. Then the best fermentation condition was investigated for maximum biosurfactant production and finally biosurfactant identity was investigated using some chemical and spectroscopy methods. The maximum biosurfactant production by B. subtilis PTCC 1023 was obtained when it was grown in brain-heart broth medium containing FeSO4 (4×10-3 M), MnSO4 (1.3×10-3 M), starch (4%) and castor oil (4%) which incubated in a 300 rpm rotary shaker at 30°C for 24 h. Lipopepetide natures in this biosurfactant was confirmed by biochemical and spectroscopic methods

Nordiska äpplen - projekt NordApp

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Antitumor and antibacterial activity of four fractions from Heracleum persicum Desf. and Cinnamomum zeylanicum Blume

At the present study tumor inhibition and antibacterial activity of the essential oils of Heracleum persicum and Cinnamomum zeylanicum was investigated. Methanol and petroleum ether were extracted from C. zeylanicum by potato disk method. These fractions showed cytotoxic effects in brine shrimp lethality assay (BSL). The authors found both H. persicum (57.16%) and C. zeylanicum (72.90%) had inhibition effects on Agrobacterium tumefaciens which induced crown gall tumor on potato disk. These oils also exhibited antitumor activity where IC50 was applied and the values were 2.24 and 1.20 mg/mL, respectively, for H. persicum and C. zeylanicum. C. zeylanicum also inhibited the growth of all tested Gram- positive and Gram-negative strains. In all, the findings of the present study completely correspond to the results obtained in brine shrimp lethality

Nordiska äpplen – projekt NordApp

Frukt av många olika slag odlas över hela världen, och utgör en viktig del av den totala livsmedelsförsörjningen. I varmare länder är mångfalden stor – former och färger bildar en förförande palett om man besöker en fruktmarknad, liksom doft och smak hos de frukter man väljer att bekanta sig närmare med. I de nordiska länderna sätter klimatet dessvärre stopp för merparten av dessa frukter – men vi har lyckligtvis några, främst kärn- och stenfrukter inom familjen Rosaceae. Äpple har sålunda odlats i de nordiska länderna sedan början av medeltiden, och detta är numera vår i särklass viktigaste frukt, såväl kulturellt som ekonomiskt. Vissa utländska äpplesorter fungerar ganska bra i odling även på våra breddgrader men för merparten blir den korta vegetationsperioden och de stränga vintrarna övermäktiga hinder. Offentligt finansierade växtförädlingsprogram har därför bedrivits i Finland, Norge och Sverige för att ta fram klimatanpassade sorter. På senare tid har ökad omsorg om miljö och hälsa aktualiserat ytterligare ett förädlingsmål: resistens mot olika skadegörare